The invention relates to a fixed calliper motor vehicle disk brake including:                a disk,        a calliper casing that straddles the disk,        at least one brake pad that is adapted to co-operate with a facing lateral face of the brake disk, and        at least one piston that is mounted to slide axially in a complementary cylinder of the casing and that co-operates with said brake pad to urge it axially in the direction of said lateral face,and in which the calliper casing includes, associated with said at least one brake pad, means for mounting this brake pad and guiding axial sliding thereof relative to the casing.        
As a general rule, in a fixed calliper disk brake, the main component is the casing of the calliper, which is a component fastened to a portion of the vehicle, for example a front stub axle, and which radially straddles the outer periphery of a rotating brake disk constrained to rotate with a wheel to be braked.
On respective opposite sides of the disk, hydraulic cylinders (at least one on each side of the disk) in which pistons move by sliding axially are formed in the casing of the calliper.
Brake pads, of which there are generally two, are each placed between at least one piston and the facing annular face of the disk, and hydraulic pressure introduced into the cylinders presses the piston or pistons onto the facing face of the brake pad, and consequently onto the disk.
In known manner, the casing of the calliper is generally made in two parts or two pieces bolted or screwed together, blind bores being machined in each of these two parts to constitute the cylinders receiving the pistons.
The brake pads are accommodated in and guided to slide axially in associated and opposite housings which, for each brake pad, are formed in the associated part or half-casing.
Faces of each housing are designed to guide the associated brake pad, retaining it in position and anchoring it.
The design of the means for mounting the brake pad and guiding its axial sliding relative to the casing is particularly important for the correct operation of such a brake, and notably to solve various problems and for example to prevent the occurrence of unwanted impact noises audible to the driver of the vehicle on contact between the brake pad and the associated parts of the calliper casing.